Vortex device for obtaining both hot and cold air from a single air supply input



2, 1965 R. R. PALMISANO EI'AL 3,214,923

VORTEX DEVICE FOR OBTAINING BOTH HOT AND COLD AIR FROM A SINGLE AIR SUPPLY INPUT Filed Oct. 26, 1964 .nT rlullllllllil A L INVENTORS R RlCHARD ALwsANq f QHN A.DRAGER ATTORNEYS United States Patent VGRTEX DEVICE FOR OBTAINING BOTH HOT AND COLD AIR FROM A SINGLE AIR SUP- PLY INPUT Rocco Richard Palmisano, Bethesda, Md., and John A. Drager, Cambridge, Mass, assignors to the United States of America as represented by the Secretary of the Army Filed Oct. 26, 1964, Ser. No. 406,625 12 Claims. (CI. 62-5) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to us of any royalty thereon.

This invention relates generally to a method and apparatus for producing hot and cold gaseous streams from a pressurized stream of gas. More particularly, the present invention relates to a method and apparatus for producing hot and cold gaseous streams from a gas moving with a vortex motion.

The vortex tube, also referred to as the Ranque tube, has been well known in the art since the discovery of the basic idea by Georges I. Ranque in 1931. US. Patent No. 1,952,281, issued March 27, 1934 to Ranque, discloses the details of the vortex tube and its operation from which a hot and cold gas is obtained when the incoming gas is moving with a vortex motion. Several bibliographies covering the field have been published concerning the vortex tube, among which are the W. Curley and R. MacGee, Jr., Refrigeration Engineering," volume 59, 1951, pages 166 and 191 to 193, and Bibliograph and Survey of the Vortex Tube, by R. Westley, College of Aeronautics, Cranfield, England.

As is conventional in the art, the vortex tube may include a chamber having the shape of a surface of revolution, such as a cylinder, this chamber having an inlet pipe for tangentially introducing the gas to be treated into a central region of the chamber. A gyratory motion is imparted to the gas as it enters the chamber, and means are provided to divide the gas into two concentric sheets moving along each other. If part of the gas is discharged at a point in or near the center line of the tube and another part at a point on the periphery of the tube, the result is that the former part has become colder and the latter part warmer than the entering gas. This phenomenon, which occurs in the vortex tube during expansion of the gas, is referred to as the heat separation effect. This heat separation effect results in the vortex tube (in an uncooled tube) becoming hot at least for a portion thereof, and this will be referred to as the hot side of the vortex tube.

Various improvements have been made in the basic concept which attempt to improve the heat separation effect. For instance, present day vortex tubes embodying the Ranque concept may achieve well over 100 F. difference in temperature between the hot and cold outlets. However, while the potential of the vortex tube has been in focus with those familiar with its operation, practical applications of the vortex tube have not been numerous. One of the reasons the vortex tube has not been used extensively is that the tube heretofore was thought to require considerable length. This length, which may frequently be 12 inches or more, has been a handicap to the use of the vortex as a simple personal air conditioner under protective clothing of any kind. Heretofore protective clothing, such as a two-piece suit of a polyvinyl chloride .006 inch thick, has been cooled by a central distributing system with a portable compressor that may be strapped to the wearers back. With a vortex tube only, a source of high pressure air is necessary.

3,214,923 Patented Nov. 2, 1965 For the comfort and convenience of the wearer, the tube is desirably as short as possible.

Accordingly, one of the principal objects of the present invention is to provide a vortex tube and a method for producing hot and cold gas in a simple device which is of small dimension.

Another object of the present invention is to maintain hot and cold gas streams separate to improve the heat separation effect.

Another object of the present invention is to remove the hot gas from a point adjacent the gas inlet.

A further object of the present invention is to obtain cool gas by expansion of the gas into a lower pressure chamber.

These and other objects and advantages of the present invention will become apparent to those skilled in the art, from the following description when read in conjunction with the accompanying drawing, wherein:

FIGURE 1 is a perspective view of the vortex tube in accordance with the present invention;

FIGURE 2 is a side elevational view partly broken away showing the details of the vortex tube and accompanying valves;

FIGURE 3 is a cross sectional view taken along line 3-3 of FIGURE 2.

Briefly, the present invention includes a method of obtaining from a stream of compressible fluid under pressure a stream of hot fluid and a stream of cold fluid by means of steps of flowing the compressed fluid from an inlet in a vortex motion along a surface of revolution in a first chamber, removing a hot fluid stream from an out let adjacent the inlet and along the axis of the vortex, Withdrawing a portion of the compressible fluid while in angular vortex motion, and then expanding and cooling this fluid portion in a chamber of reduced pressure to produce a cold fluid.

The apparatus, briefly, is described as a chamber having the shape of a body of revolution which includes a front wall and a. diaphragm wall, in inlet for the compressible fluid positioned on the surface of the body of revolution, and adjacent the front wall, a hot fluid outlet positioned within the front wall and along the axis of the body of revolution, thus the hot fluid outlet being adjacent the inlet in a manner contrary to the Ranque concept, providing an opening in the diaphragm wall, a second chamber which fluidly communicates with the front chamber through the opening and is at a pressure lower than the pressure of the first chamber, and a cold fluid outlet positioned within a rear wall forming a part of the second chamber.

The vortex tube is shown generally at 10 and includes a body 12 and is in the shape of a body of revolution, such as a cylinder. The vortex tube may be made from conventional plastic materials which can withstand temperatures which may rise as high as 300 F. and also withstand the pressure of the incoming gas which may run as high as p.s.i.g. The body 12 may be precast of metal in a manner well known in the art, or the various parts may be bolted or Welded together.

The vortex tube is provided with a front wall 14 and a rear wall 16, which has a hot fluid outlet 18. A gaseous fluid inlet 22 is provided through the body 12 and is adjacent the front wall 14, and thus also adjacent the hot fluid outlet 18.

The vortex tube is partitioned by at least one diaphragm 24, which has an opening 26 therein. Within the vortex tube between the diaphragm wall 24 and the front wall 14 a first chamber 28 is formed, in which vortex motion of the gas is achieved. The axis of the chamber and vortex tube may be considered the axis of the vortex produced by the eccentric positioning of the inlet 22.

Actually, as shown, inlet 22 is tangential to chamber 28; however, this positioning is not critical, since it is important only that axis X of the inlet and axis Y of the vortex do not intersect, and in this manner motion will be imparted to the fluid exiting from the inlet 22, which, by the fact that chamber 28 is formed in the shape of a revolution, will produce the necessary vortex.

The size of the first chamber 28 is not critical, except that it has been found that the diaphragm 24 should be at a distance from front wall 14 of not more than three times the diameter of the inlet 22. The reason for this is that if the chamber is too large and the pressure of the gas entering through inlet 22 not high enough to produce a vortex within chamber 28, the efliciency and effectiveness of the first chamber will be considerably diminished. On the other hand, as long as a vortex is produced by the incoming gas, the gas exiting through outlet 18 will be hot.

Adjacent the first chamber is at least one additional chamber 30 formed by diaphragm wall 24, which is similar to the previously mentioned diaphragm wall. The additional diaphragm wall has an opening 26 exactly as the diaphragm wall of the first chamber. As shown in FIG- URE 2, there are a total of four diaphragms 24, each pro vided with an opening 26 and each forming successively chambers 31, 32, and 33, which may be similar to chamber 30. These chambers act as expansion chambers, since they will be at a lower pressure than the pressure in chamber 28, and in fact will be at a lower pressure the closer the chamber is to the cold air outlet 20. The size and number of these chambers is optional, it being important only that there be at least one such chamber adjacent chamber 28, in order for the portion of the gas exciting through opening 26 in the diaphragm wall forming chamber 28 to expand sufliciently to be cooled. It is also important that the fluid outlet 18 be adjacent inlet 22, and in any event considerably closer to the inlet 22 than the cold fluid outlet 20 is to the inlet 22. Since it is important only that the gas portion exiting from chamber 28 be expanded by being cooled, it has been found that it is not critical to have the opening 26 aligned with the axis Y of the vortex; however, such construction is preferable.

Shown attached to either end of vortex tube 10, at 34, are conventional ball valve assemblies 35, provided with the usual ball valve 36, and shank 38 with handle 40. This type of ball valve is conventional and does not form a part of the present invention.

The method in accordance with the present invention from which hot and cold streams may be obtained from a stream of compressible fluid is achieved by means of a vortex tube which may have the following dimensions:

Inches Inlet diameter .25 Outlet diameters, both .25 Distance of first diaphragm wall 24 from front wall 14 .4 Width of chambers 30, 31, 32 .25 Width of chamber 33 .312 Overall length measured from front wall 14 to rear wall 16 2.125

The compressible fluid air under pressure of 40 pounds per square inch was forced through the inlet eccentric to the axis of chamber 28 to form a vortex within chamber 28. This vortex motion heats the air, the air being hotter at the axis of the vortex than at the periphery. The hot air is then removed from outlet 18 along the axis of the vortex created and is found to be 128 F., while the remaining gas under pressure is withdrawn through openings in the chambers and successively into chambers 30, .31, 32, and 33, which expand and cool the gas. As the gas passes from one chamber to the next, further cooling is achieved. Finally the gas exits at outlet 20 at a temperature of 48 F., thus achieving a separation effect (dT) of F. As would be expected, greater increase in inlet pressure will increase the heat separation effect, giving in particular a higher temperature for the hot fluid outlet.

In achieving the most desirable results of the present invention, the hot fluid stream should be removed essentially from along the axis of the vortex, where it would be expected to have the greatest angular velocity which conforms to the law of constant angular momentum. It is because of the constant angular momentum, wherein the angular velocity is greater at or near the axis of the vortex, that the friction of the molecules of gas is most noticeable, thus causing the high temperature.

A vortex tube of this type, because of its small dimensions, may be readily adaptable for use in areas requiring small dimensions, such as in personal protective clothing, thus fulfilling the objects of the present invention. From the foregoing detailed description it will be evident that there are a number of changes, adaptations, and modifications of the present invention which come within the province of those skilled in the art; however, it is intended that all such variations not departing from the spirit of the invention be considered as within the scope thereof as limited solely by the appended claims.

We claim:

1. A method of obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

causing said compressible fluid to flow from an inlet in a vortex motion along a surface of revolution in a first chamber,

removing a hot fluid stream from an outlet along the axis of the vortex and adjacent the inlet,

withdrawing a portion of said compressible fluid while in angular motion,

expanding and cooling said fluid portion into a second chamber of reduced pressure to produce a cold fluid, and

removing cold fluid.

2. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front wall,

a hot fluid outlet positioned within said front wall and along the axis of said body of revolution,

an opening in said diaphragm wall,

a second chamber in fluid communication with said first chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear wall, and

a cold fluid outlet positioned within said rear wall.

3. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front Wall,

the axis of said inlet being in a different plane from the axis of said body of revolution,

a hot fluid outlet positioned within said front wall and along the axis of said body of revolution,

an opening in said diaphragm wall,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear wall, and

a cold fluid outlet positioned within said rear wall.

4. The apparatus of claim 3, wherein the inlet is tangential to said surface.

5. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm Wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front wall,

a hot fluid outlet positioned within said front wall and along the axis of said body of revolution,

an opening in said diaphragm wall,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear Wall,

a cold fluid outlet positioned within said rear wall, and

said hot fluid outlet being positioned substantially closer to said inlet than said cold fluid outlet is positioned to said inlet.

6. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front wall,

a hot fluid outlet positioned within said front wall and along the axis of said body of revolution,

an opening in said diaphragm Wall along the axis of said body of revolution,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear wall, and

a cold fluid outlet positioned within said rear Wall.

7. The apparatus of claim 2, wherein a plurality of other diaphragm walls mutually parallel are positioned rearwardly of said diaphragm wall and forwardly of said rear wall, thereby forming succesive chambers of successively reduced pressure.

8. An apparatus for obtaining from a stream of compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front Wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front wall,

said diaphragm being at a distance from "said inlet of not greater than three times the diameter of said inlet,

a hot fluid outlet positioned within said front Wall and along the axis of said body of revolution,

an opening in said diaphragm Wall,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear wall, and

a cold fluid outlet positioned within said rear wall.

9. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front wall,

a hot fluid outlet positioned within said front wall and along the axis of said body of revolution,

an opening in said diaphragm wall along the axis of said body of revolution,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear wall,

a cold fluid outlet positioned within said rear wall, and

said hot fluid outlet being positioned substantially closer to said inlet than said cold fluid outlet is positioned to said inlet.

10. An apparatus for obtaining from a stream of a compressible fluid under pressure a stream of hot fluid and a stream of cold fluid comprising:

a first chamber having the shape of a body of revolution and including a front wall and a diaphragm wall,

an inlet for said compressible fluid positioned on the surface of the body of revolution, and adjacent said front Wall,

the axis of said inlet being in a different plane from the axis of said body of revolution,

said diaphragm being at a distance from said inlet of not greater than three times the diameter of said inlet,

a hot fluid outlet positioned within said front Wall and along the axis of said body of revolution,

an opening in said diaphragm Wall along the axis of said body of revolution,

a second chamber in fluid communication with said front chamber through said opening and at a lower pressure than the pressure of said first chamber,

said second chamber having a rear Wall,

a cold fluid outlet positioned within said rear wall,

and

said hot fluid outlet being positioned substantially closer to said inlet than said cold fluid outlet is positioned to said inlet.

11. The apparatus of claim 10, wherein a plurality of other diaphragm walls mutually parallel are positioned rearwardly of said diaphragm wall and forwardly of said rear wall, thereby forming successive chambers of successively reduced pressure.

12. All the improvements and advantages and features, singly and in combination, which are disclosed in either the specification or the claims.

References Cited by the Examiner UNITED STATES PATENTS 2,741,899 4/56 Von Linde 625 3,152,475 10/64 Ford 625 WILLIAM J. WYE, Primary Examiner. 

1. A METHOD FOR OBTAINING FROM A STREAM OF A COMPRESSIBLE FLUID UNDER PRESSURE A STREAM OF HOT FLUID AND A STTEAM OF COLD FLUID COMPRISING: CAUSING SAID COMPRESSIBLE FLUID TO FLOW FROM AN INLET IN A VORTEX MOTION ALONG A SURFACE OF REVOLUTION IN A FIRST CHAMBER, REMOVING A HOT FLUID STREAM FROM AN OUTLET ALONG THE AXIS OF THE VORTEX AND ADJACENT THE INLET, WITHDRAWING A PORTION OF SAID COMPRESSIBLE FLUID WHILE IN ANGULAR MOTION, EXPANDING AND COOLING SAID FLUID PORTION INTO A SECOND CHAMBER OF REDUCED PRESSURE TO PRODUCE A COLD FLUID, AND REMOVING COLD FLUID. 